package com.itheima.reggie.service;

import com.itheima.reggie.entity.ShoppingCart;

import java.util.List;

public interface ShoppingCartService {

    /**
     * 删减购物车里面数量
     * @param shoppingCart
     * @return
     */
    public ShoppingCart sub(ShoppingCart shoppingCart);

    /**
     * 添加到购物车
     * @param shoppingCart
     * @return
     */
    public ShoppingCart add(ShoppingCart shoppingCart);

    /**
     * 查看购物车数据;
     *
     * @return
     */
    public List<ShoppingCart> selectList();

    /**
     * 清空购物车
     *
     * @return
     */
    public int deleteAll();
}
